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By Steve Kral

Americans are taking a more critical view of various environmental laws because the effects of those laws are becoming more pervasive and intrusive, according to William Perry Pendley. And Secretary of the Interior Bruce Babbitt is seemingly so unpopular in the West, he no longer campaigns there for Clinton Administration policies. Pendley is president and chief legal officer of the Mountain States Legal Foundation, a public service, non-profit law association that takes on property rights cases for people who cannot afford representation. He was one of the luncheon speakers at the 101st Northwest Mining Association meeting, held in Spokane, WA in early December.

Jan 1, 1996

By Ben V. Petersen

Surveying is to tunneling, as a steering wheel is to a car—somewhat essential if you want to end up in the right place. The principles of tunnel surveying have remained unchanged since the first tunnels were constructed: To mathematically connect the selected start and end points of a tunnel and physically translate that alignment onto the ground. The alternative is just dead-reckoning and leaves the probably less than satisfying end results to chance. Today’s laser-guided tunnels often have to thread the needle through a maze of soil types, utilities, structural features and other underground considerations. Surveying makes it possible.

Jan 1, 2005

By V. T. McLemore

"Production of industrial minerals remains important to the rural economy of New Mexico. In 2014, some 240 mines were registered in New Mexico, including 25 industrial mineral operations and 189 aggregate operations. New Mexico leads domestic production of potash, perlite, zeolite, and travertine. Other production includes aggregate, humate, pumice, gypsum, salt, common and fire clay, scoria, limestone, fly ash, cement, magnetite, silica, and decorative stone. New Mexico has potential for additional production of industrial minerals. One company is exploring for garnet. Cretaceous black sandstones in the San Juan Basin have drawn interest for titanium, rare earth elements (REE), and zircon. Other REE deposits are being explored. REE-Th-U veins are found in the Gallinas, Capitan, and Cornudas Mountains and Laughlin Peak-Chico Hills. Recent exploration has occurred for beryllium in the San Mateo Mountains, Iron Mountain, and Victorio districts. Companies also are examining High-Ca limestone and High-Mg dolomite for potential development. Aggregate continues to be important in urban areas and along highways. INTRODUCTION Industrial minerals and rocks are literally the building blocks of our way of life and they are an exceptionally diverse and vital group of raw materials that underpin almost all aspects of human activity, infrastructure, and standard of living. Industrial minerals and rocks are used in the manufacture of many products, from ceramics to plastics and refractories to paper. Although industrial minerals permeate every aspect of daily life, their presence and their role are typically invisible. A widely used definition of industrial minerals and rocks is “any rock, mineral, or other naturally occurring substance of economic value, exclusive of metal ores, mineral fuels, and gemstones: one of the non-metallics” (Bates, 1975). This definition includes the important construction materials sector as well as specialized industrial minerals, but complex interactions between consumer industries produce a number of apparent anomalies to this definition. Some metals are included as industrial minerals because their use is industrial rather than as a metal. Sulfur is now predominantly extracted as a by-product of cleaning natural gas, one of the world's major energy fuels. Production of industrial minerals has been and remains important to the rural economy of New Mexico. Industrial minerals constitute nearly 40% of the more than $2.8 billion generated by mineral production in New Mexico in 2013 (Table 1, see APPENDIX). In 2015, some 240 mines were registered in New Mexico. This total includes 25 industrial mineral operations and 189 aggregate operations. New Mexico leads domestic production in potash, perlite, zeolite, and travertine. Other industrial minerals production from New Mexico includes aggregate, humate, pumice, gypsum, salt, common and fire clay, scoria, limestone, fly ash, cement, magnetite, silica, and decorative stone. Additional production statistics are in Harben et al. (2008). Major industrial mineral districts are shown in Figure 1."

Jan 1, 2016

By Konstantinos Komnitsas, Evangelos Petrakis, Emmanouil Varouchakis

During the modeling of grinding systems, population balance modeling (PBM) which considers a constant breakage rate has been widely used over the past years. However, in some cases, PBM exhibited some limitations, and time-dependent approaches have been developed. Recently, a non-linear framework which considers the traditional linear theory of the PBM as a partial case was introduced, thus allowing the estimation of product particle size distribution in relation to grinding time or the specific energy input to the mill. In the proposed model the simplified form of the fundamental batch grinding equation was transformed into the well-known Rosin–Rammler (RR) distribution. Besides, the adaptability and reliability of the prediction model are among others dependent upon the operating conditions of the mill and the adjustment of the RR distribution to the experimental data. In this study, a series of grinding tests were performed using marble as test material, and the adaptability of the non-linear model was investigated using three loads of single size media, i.e., 40, 25.4, and 12.7 mm. The results indicate that the proposed model enables a more accurate analysis of grinding, compared to PBM, for different operating conditions.

Jun 24, 2023

By Francis F. Pitard

North America had an Important role in the early development of sampling theories. Unfortunately many progressive ideas were soon frozen into a series of guidelines based on the philosophy that "honest sampling only requires good judgment and practical experience". Such a philosophy appeared to be good enough In the early age of the mining Industry; however, it became quickly necessary to find new approaches. During the last thirty years, Pierre Gy's sampling theory provided tremendous breakthrough in the comprehension of this new science, nevertheless went unnoticed in North America. Sampling always generates complex problems and as the philosopher and mathematician Descartes suggested: "A complex problem can often be dissociated Into a series of several simpler problems, only then you try to solve those one by one". The only way to solve sampling problems is to consider each component of the overall sampling error: components of a continuous model such as long-range quality fluctuations, periodic quality fluctuations, weighting fluctuations; components of a discrete model such as materialization errors, delimitations errors, extraction errors, fundamental errors, grouping errors, and segregation errors. PAST AND CURRENT PRACTICES Many sampling methodologies have been developed, improved, and standardized during the first half of this century. Accordingly, sampling equipment has been proposed, selected, and used by standards committees. Today, there is a tremendous variety of sampling methodologies and corresponding tools offered to anyone with limited experience in sampling and it is very easy for a chemist, metallurgist, geologist or miner to spend considerable money in equipment transgressing the most basic rules of sampling correctness. Sampling stations that never worked properly in modern plants often cause engineers to abandon them and return to a primitive form of grab sampling.

Jan 1, 1986

Sandvik built its first stone crusher in 1896 and has since grown to become a world leader in mining equipment. ?We are the best in the world, and we can now be even better at making our cone and jaw crushers in different models,? Olle Lundberg, production engineer at the Sandvik Mining factory in Svedala, Sweden told freelance journalist U. Samuelsson, of mekpoint.com. As a specialty manufacturing business under the umbrella of the Sandvik Group, Sandvik Mining is a leading global supplier of equipment, tools, services and technical solutions for the mining industry. Its expertise covers the areas of rock drilling, cutting and crushing, as well as loading, hauling and the handling of materials. Lundberg, along with five colleagues, will write CNC programs for the lathes and machining centers that manufacture Sandvik?s specially constructed casting. In 1999, Sandvik chose ESPRIT computer-aided-manufacturing (CAM) software by DP Technology to program its array of machine tools, and has worked with ESPRIT reseller Holotech, based in Örebro, since 2003.

Jan 1, 2014

By E. Tondu

Separation Technologies Inc.’s (STI) electrostatic separation technology is a dry, continuous process for the separation of discrete particles. This high-volume process does not require any additives nor is any additional waste produced. In December 1993, STI, in cooperation with New England Power(NEP), installed an 18-t/h (20-stph) prototype electrostatic separator at NEP’s Salem Harbor plant. The plan was to convert waste streams of type F fly ash into commercially valuable products. In July 1995, a second separator was installed at NEP’s Brayton Pointplant. Fly ash feed, ranging from 6% to 25% carbon (loss-of-ignition fly ash or LOI), is separated into <3% LOI “clean” ash and sold as a portland cement substitute in the New England concrete markets.

Jan 1, 1996

By T. Krichler

"Current mine control stations are either single-position systems with high engineering effort or all-in-a-box solutions with low integration possibilities of third-party devices. Above all, both approaches are cost-intensive and not feasible for small companies. This paper shall be an inspiration of how to enhance the productivity and monitoring of an existing mining system in a modular way by introducing a proven technique of the ongoing digital revolution: A Wi-Fi network based on the communication protocol OPC UA. The starter kit consists of a single-board computer, a WLAN access point and any electronic sensor. INTRODUCTION The majority of the European mining industry is run by small and medium deposits (Europe Geology, 2017). This is due to the fact that most ore mines in Europe are widely distributed within the continent, are generally small and additionally they are often steeply inclined. Such ore bodies are normally mined with underground mining methods and must be excavated with high selectivity because of their small thickness. That is why the economy of scales, higher efficiency through bigger machines, cannot be used in most deposits in Europe except for lignite mines. It is important to find an alternative possibility to improve the efficiency of European mines for making them competitive internationally. For cost optimization and profit maximization it is necessary to use the trends of industry 4.0 and to broadcast these into the mining industry to reach a technological advantage. The goals of the EU within the Horizon 2020 funded project are to shorten the actualisation of the mine and block model to hours, improve the communication with Through the Earth (TTE) via very- or ultra-low frequency for long-time monitoring of the abandoned workings, and develop a cost-effective mine control station for optimization of mining processes in Small and Medium Enterprises (SMEs) as well. This paper deals specifically with the new approach for data acquisition, transmission and visualisation of a mine. SCADA AND ERP IN MINING There are already many Supervisory Control and Data Acquisition (SCADA) and Enterprise Resource Planning (ERP) programs on the market, but these are normally not developed for the mining industry. At the moment this leads to three options. • To hire a system integrator, who shall build a complete control station for one mine that requires a high amount of knowledge in programming and cannot be maintained by the mining company itself. • To buy different types of out-of-the-box systems, whereby every system can include some of the used technology. In this case a huge amount of project engineers and operators – at least one per system and shift- is required. • To buy every machine and program from one company including the service contracts."

Jan 1, 2018

By Michael P. Evans

Traditionally in coal processing jigs have been used to clean the coarse coal fraction, the +3/8" or +1/4" material. Today with the advent of modern fine coal jigs in the United States, its place was moved from the coarse to the inter- mediate coal circuit, the 3/8" x 100 mesh. The most economical coarse coal circuit to build and operate is a heavy media bath circuit. The following table summarizes the cost per raw coal ton processed for a coarse coal jig circuit, and a coarse coal heavy media bath circuit. The flowsheets used to compare these two circuits are shown in Figures 1 and 2.

Jan 1, 1983

By Rameshwar Sah, Somasekhar Pitchika, Akhil Singh, Seenivasan Rajiah, C. B. Dayanand, G. Balachandran

In the sintering of iron ores, the partial substitution of anthracite coal for coke breeze has been considered to be an effective way of reducing emissions and improvement in sintering properties. In the present study, the combustion characteristics of the anthracite coal and coke breeze were investigated and its influence on product sinter quality and sinter flue gases is being monitored. Pot trials are carried out with different coke breeze ratios, 0%, 40%, 50%, 60%, and 100%. It is found that as the percentage of anthracite coal is increased from 0 to 100%, the sintering time decreased from 24 to 20 min, and the productivity increased from 2.25 to 2.60 t/h/m2. Up to 60% anthracite coal substitution Tumbler index (+ 6.3 mm%), Product yield (+ 5 mm%), and fines generation (− 5 mm%) is found 62.29%, 85.17%, and 15.33%; moreover, hematite ( Fe2O3), magnetite ( Fe3O4), calcium ferrite phases ( CaFe2O4, CaFe3O5), and Silico ferrite of calcium and aluminum (SFCA) are major mineral phases found during microstructural analysis of product sinter. Keywords Sintering · Anthracite coal · Combustion rate · Productivity

Jun 2, 2022

By A. L. Wilder

Coeur d&apos;Alene Mines Corporation&apos;s newest precious metals property is located in the old Rochester Mining District approximately twenty-five miles northeast of Lovelock, Nevada. Built at an elevation in excess of 6 000 feet, the Coeur-Rochester gold silver heap leach property encountered cold weather operational problems typical of most northern Nevada heap leach properties, soon after the start-up of operations last fall. Due to the size of the heap area under leach at Rochester, it was decided that 1 the usual practice of spraying to an "ice field" and waiting for the spring thaw was impractical. Further, the delivery schedule for a solution heating system of the size required was unacceptable. Accordingly, Rochester personnel embarked on a program to seek out a leach solution distribution system that would enable an operation through the winter and yet be cost effective. The findings of this program were rather dramatic and, as a result, the whole perception of heap leach solution application at Rochester has changed forever.

Jan 1, 1988

By T. Doshi, S. Ennis

The interactions of mineralogy, chemistry and mechanics in an ore concentrator are highly complex, so it can be particularly hard to measure the impact of a specific plant change. This paper describes a method for modeling a baseline metal recovery so that the value of a major process improvement can be measured. This method only considers variables that cannot be optimized, such as mineralogy or equipment availability. Linear regression, random forests, extreme gradient boosting (XGB), and simple two-layer neural network models of process value were tested as candidate baseline model types to assess the impact on throughput and recovery in a copper concentrator. XGB performed the best in terms of accuracy for both throughput and recovery models. Using an XGB model of nonoptimizable process variables provides an accurate, dynamic baseline that can be compared with continuous production data to determine the value added by major concentrator improvements in real time.

Mar 2, 2022

By Thomas E. Ban

During recent years fuel consuming industries of the United States have been caught between environmental restrictions and the uncertainty of obtaining an inexpensive fuel. With the advent of the National Energy Act of 1978 there has been added impetus to switch from gas and oil to coal. For industrial furnaces and boilers that were designed to bum coal, returning to an available compliance coal might be feasible. However, furnaces and boilers designed for gas or oil cannot reasonably be converted to coal unless the coal is initially gasified. All cases, nevertheless, depend upon the availability of an adequate structured coal of a compliance composition, a challenge to the coal mining industry. The foregoing problems have contributed to the current energy-coal crisis of today&apos;s economies. It therefore would be worthwhile to capitalize on previous experiences of the mineral processing industry.

Jan 1, 1979

By Isabel F. Barton, Matthew J. Gabriel, CARSON ROBERTS, JOHN LYONS-BARAL, LEON DUPLESSIS, Mark D. Barton

Geometallurgical assessment of orebodies in the mining industry typically relies on bench-scale or lab-based characterization techniques. In this study, we investigate drone- and tripod-based field hyperspectral imaging as a potential addition to the geometallurgy toolkit in multiple applications. This pilot study tests hyperspectral imaging for largescale mineral mapping in and around the active Lisbon Valley copper mine, including natural exposures, previously producing U-V mines, highwalls, dumps, and leaching sites. Tests include different (supervised and unsupervised) mineral data classification methods, varying mineral spectral reference libraries, comparison with ground-truth geological and spectroscopic mapping and sampling, and integration with LiDAR data. The results show that hyperspectral scans can produce spatially registered maps of the distribution of different spectrally active mineral types over dumps, highwalls, leach pads, and natural outcrops. Clays, other phyllosilicates, carbonates, and sulfates showed up particularly well. The sensor was also able to distinguish dry from lixiviant-saturated areas and map different clay types on the leach pads, and shows promise for differentiating types and health of vegetation. These results suggest that hyperspectral imaging, if coupled with robust ground-truthing, can be a useful complement to existing geometallurgical techniques in the mining industry, such as geological mapping, blast hole sampling and automated mineralogy identifications, and handheld spectrometry. In particular, hyperspectral imaging has promise for mapping the distribution of acid-consuming minerals; mapping the distribution of swelling, sliming, and heap-blinding clays; and pinpointing problem areas on heap leach pad surfaces.

Feb 10, 2021

By J. Iannicelli

Spray drying is the principal drying method used in the production of over six million tons annually of beneficiated kaolin in Georgia. Thirty-three dryers in the Georgia Kaolin belt comprise the highest concentration of large tonnage spray dryers in the world. The steady growth of spray drying in the U.S. kaolin industry is paced by advances in design and development of large spray dryers which have led to large scale new applications in mining and related industries.

Jan 1, 1982

By Christian F. Baiz

The author will present a discussion of the steps which must be taken by the prospective developer of a small mining operation to establish technical credibility when seeking financial backing. Particular emphasis will be given to the differing levels of technical work (and their relative cost) which must be accomplished to supply the information necessary to satisfy potential investor groups, whether they be other mining companies, equity investors, or financial institutions such as venture capital firms or commercial banks.

Jan 1, 1981

By M. P. Smith, C. Hughes-Narborough, Y. T. Man

"Money and reputations can be lost in bad projects. Causes of bad mineral processing projects include poor contract definition and purchase of equipment without adequate test work. However, the root cause of many of the problems that can lead to bad projects is not any inanimate object, bad weather or catastrophic natural event but the people working on the projects. Because the people are so critical to the success of a mineral processing project, one must have suitably qualified and experienced people (SQEP) in all key positions. Characteristics that define SQEP include people who have successfully executed projects of similar size before; have undertaken projects treating the same minerals and producing the same valuable products and people who are familiar with designing, operating and implementing the required technologies and unit operations.To minimize the likelihood of future bad mineral processing projects, five recommendations are put forward in relation to the people aspect of a project.1. Attempt to retain SQEP during any down turn in the mining economic cycle so thatthe knowledge and experience can be kept within the industry.2. Increase the effort in attracting young people into the industry and retaining them.3. Set up robust training program to give young professionals a firm foundation of what real life projects and operations are like.4. Provide mentoring and continuous training for people after they have completed their formal graduate training program. Their career progression should be appropriately monitored and controlled.5. People working in projects must be exposed to as many detailed design and other finer issues as possible so that they can comprehend the amount of work required to deliver a project successfully."

Aug 1, 2016

By J. Drimmer

The past several decades have seen the rapid expansion of multinational mining companies? exploration and production activities around the globe. This trend has resulted from a number of factors, including increased demand for resources as a result of worldwide economic growth, the diminishment of known and proven reserves, rising commodity prices, technology improvements, and the liberalization of investment regimes in developing countries with significant natural resources. With those opportunities, however, come associated risks and significantly increased legal compliance obligations that may be imposed by various bodies. That includes domestic regulations, as well as foreign civil and criminal laws with extraterritorial reach. A failure to adhere to those laws can have dire consequences, including substantial monetary fines and penalties, severe damage to a company?s reputation, and even jail time for individual company employees.

Jan 1, 2010

By Richard E. Gray

Virtually all structures show some signs of distress due to deterioration of the building components, to changed loads, or to changed support conditions. Changed support conditions result from ground movements. In mining regions many cases of structural distress are attributed to mining without considering alternative causes. This is particularly true of coal mining since it occurs under extensive areas. Coal mining is estimated to have already undermined more than eight million acres and may eventually undermine 40 million acres in the United States (HRB Singer, Inc., 1977). Other nonmetal and metal underground mines impact much smaller areas. Although it is sometimes difficult, even with careful study, to identify the actual cause of damage, persons responsible for underground coal mining should at least be aware of possible causes of building stress other than mine subsidence. This paper presents information on distress to structures and briefly reviews a number of causes of ground movements other than subsidence: Mass movements, dissolution, erosion, frost action, shrinking and swelling, yield into excavations and compressibility

Jan 1, 1986

By M. D. Ballain, V. C. Storhok, B. Pesic, J. C. Sever

Northwest Alloys, a wholly owned subsidiary of Alcoa, produces magnesium from dolomite by reduction with ferrosilicon and aluminum. This process produces alkaline by-products in quantities that allow their consideration for use as commercial by-products. Two such products are dicalcium silicate slag, Di-Cal, and magnesium oxide condensate, MgO. The alkaline properties of these materials offer acid neutralizing capability comparable to the traditionally used lime, therefore, warranting a study for their use in applications where the neutralization of acidic waters or process solutions is required, such as treatment of mine waters. In this ongoing study, three mine waters (Bunker HillMine, Berkeley Pit, and Blackbird Mine) were selected for treatment with Di-Cal and MgO. Lime was used as the background control. The solid precipitates were subsequently contacted with pure water at four different pH conditions for stability testing of prepared metal precipitates (expanded TCLP). It was found that neutralization with Di-Cal results in precipitates which are of equivalent to superior stability than those from lime treatment.

Jan 1, 1999